Fouling of surfaces exposed to an aquatic environment is a serious problem. For example, surfaces of ships such as the hull, offshore marine structures such as oil rigs, sea water conduit systems for seaside plants, buoys, heat-exchangers, cooling towers, de-salination equipment, filtration membranes, docks, and the like may all experience some degree of fouling when continually exposed to water. In the case of ships, fouling can inhibit vessel performance and capabilities. For example, fouling may substantially increase fuel consumption and may necessitate extensive and more frequent maintenance, all of which raise the overall costs of operation. Fouling may also reduce ship speed, maneuverability, and range, which impede performance. On another level, attachment of regionally specific aquatic organisms on ships that traverse the world can lead to the unwanted invasion and infestation of these organisms to non-indigenous harbors. In some instances, this can have severe adverse effects on local aquatic ecosystems.
Over the years there have been numerous attempts to minimize the effect of fouling on structures exposed to an aquatic environment. For example, coatings (e.g., paints, etc.) have been developed that impede the attachment and/or growth of aquatic organisms on such structures. Certain materials which may be used to form such a coating are described in U.S. Provisional Patent Application Ser. No. 60/506,077. Traditionally, two parallel lines of coatings research and development aimed at reducing fouling have predominated: biocide containing coatings and low surface energy, “non-stick,” fouling release coatings. Each of these approaches has produced elements of success but continue to have problems.
Unfortunately, certain biocidal coatings have been linked to environmental problems (e.g., tin based biocidal coatings, etc.). For example, while moored in harbors, paint chips and leaching have led to sediment accumulations of toxins resulting in harm or destruction of non-targeted sea life (e.g., oysters). Accordingly, the development of an effective alternative to these biocidal coatings would be desirable.